The present invention relates generally to the installation of conventional plastic expansion rivets. More particularly, the present invention is concerned with a plurality of pneumatically driven expansion rivet applicator tools suitable for quickly and easily installing plastic expansion rivets.
In the prior art plastic expansion rivets are well known. Preferably such rivets may be molded through conventional plastic injection molding techniques in a single, one piece unit. A typical expansion rivet includes an intermediate flange portion separating an integral, generally cylindrical stem from an adjacent tubular expansible segment. Such rivets may be employed to fasten a pair of workpieces together by first inserting the expansible portion through aligned, adjacent orifices. Afterwards, a mallet or tool such as a hammer or the like may be employed to ram the expansion fitting shank through the flange, coaxially interiorly of the expansion portion, thereby expanding same. Such expansion prevents subsequent withdrawal of the fitting, which secures the workpieces together.
In the aircraft industry conventional aircraft assembly demands the temporary securement of sheet metal parts together. At this time a metallic "Clico" or "Wedgelock" tool is employed to temporarily, yieldably secure aligned metallic parts together. This tool includes a rigid, metallic sleeve including an axially displaceable portion associated therewith. Forwardly projecting from the sleeve are a plurality of fork-like tongs, which are expanded when a flat tongue is projected axially forward therewithin. While such a tool will yieldably maintain two or more workpieces together (providing their apertures are aligned) the cost of such a tool is a major detriment, since a separate tool is required for each orifice group to be aligned.
While metallic rivets could be used to maintain proper operative alignment of sheet metal parts, subsequent removal of such rivets is obviously difficult and time consuming. On the other hand, if plastic expansion rivets could be employed to temporarily maintain aligned sheet metal workpieces together, their subseqent removal through drilling or the like would be quick, easy and inexpensive. Moreover, during the critical removal phase, damage to the high tolerance metallic sheet metal parts would be minimized if not altogether avoided.
Hence it is desirable to provide some form of pneumatic applicator tool for quickly and easily inserting plastic expansion rivets during aircraft assembly. Of course, such a tool would find wide application in other assembly arts where plastic expansion rivets may be installed either temporarily or permanently.